1. Field of the Invention
The invention relates generally to optoelectronic devices, method and means for optically coupling thereto.
More particularly, the invention relates to a low profile silhouette package of an optoelectronic device and an associated optical coupler.
Even more specifically, the invention relates to a planar-mounted semiconductor signal processing device having an optoelectronic device mounted generally planar thereto for assembly and then moved to a position substantially orthogonal to said substrate to provide a module package to which an optical light fiber is introduced on a line essential parallel with said planar substrate.
2. Description of the Prior Art
An optoelectronic device is an electronic device combining both optic and electric ports. Such a device may be either a light receiver, such as a photodiode, or a light transmitter, such as a light-emitting diode (LED). Frequently, it is desirable to utilize such a device as a discrete component of a hybrid circuit assembly, especially where such optoelectronic device is an LED not now able to be fabricated in monolithic form with signal processing elements.
In general, the prior art provides two methods for providing light coupling to an optoelectronic module. In the first of these, the optoelectronic device is generally planar with the substrate of the associated circuitry. Where the planar situs is employed, conventional production techniques may be utilized to provide the necessary electric connections to the electric ports of the optoelectronic device. Light coupling means, most frequently in the form of light conducting fibers, are introduced to the optoelectronic module at an angle substantially normal to the substrate plane in which the optoelectronic device lies. The light fiber is supported in an optical fiber connector and the overall assembly of optical connector and module package is somewhat reminiscent of the outline of a single story factory building having a tall smokestack rising upwards from its roof structure.
To reduce the profile of the silhouette of the optoelectronic device package, a second approach to introducing optical coupling is employed. With this alternate approach, the optoelectronic device is a discrete component mounted on a dielectric standoff above the substrate of the associated circuitry such that the plane of the optic ports of the optoelectronic device is generally perpendicular to the plane of the substrate. This configuration has distinct disadvantages in that standard production techniques for making connection to the electric ports of the optoelectronic device can no longer be utilized. Special manufacturing procedures must be devised and used to successfully produce a module of this type. However, this configuration permits the optical connector to introduce the optical fiber on a plane essentially parallel with the plane of the substrate, thus somewhat increasing the length of the package while still maintaining its low profile silhouette.
Prior art which relates to photodetector packaging and optical coupling systems may be found in U.S. Pat. Nos. 3,757,127; 4,112,308; and 4,136,357. None of this known prior art discloses apparatus or methods as disclosed herein for maintaining a low package silhouette when optically coupling to an optoelectronic module having internal electrical interconnects effected by conventional means.